Stiliyan Petrov insists Martin O’Neill’s Aston Villa side are becoming rougher, tougher and more aggressive as they lead their assault on the top four in the Premier League this season.

Villa were held to a goalless draw by Harry Redknapp’s Portsmouth on Saturday but Petrov is convinced the fact Villa managed to hold such a powerful side suggest just how far the club has come in two years since O’Neill took the reins.

He said: “It was a frustrating game for everybody. I think we started a bit too slowlyf and they had their moments and maybe two or three chances but in the second half Villa definitely dominated and, in the end, I felt we were unlucky not to score.”

Villa lie sixth in the table with Pompey seventh. Both sides face vital European matches this week with Villa entertaining Ajax in the first match of the Uefa Cup group stage on Thursday night and Pompey flying out to Portugal to face Braga.

Petrov added: “There are many positives we can take from the game. We lost 3-1 to Portsmouth at home last season and they dominated but this season we are much stronger as a squad.

“We hope now in our next game that we won’t just create chances but actually put them in. As a team, we are now getting much tougher and more aggressive in the way that we play. We are trying to be more dominant but we can still control the game with our pace and flair.”

* Villa reserves lost 2-0 to Portsmouth at Fratton Park on Monday.

Nigerian international John Utaka and Jerome Thomas scored the goals that inflicted the first defeat of the season on Kevin MacDonald’s men, who had previously beaten Stoke City, Tottenham, Arsenal and Chelsea in their first four games of the season.